The production and destruction of negative ions: Progress report, September 1, 1987-August 31, 1988

Technical Report · Fri Jan 01 04:00:00 EST 1988

OSTI ID:6967399

Pegg, D J

During the present grant period we have concentrated our efforts on investigating the structure of negative ions using the technique of fast-beam photoelectron detachment spectroscopy. A newly constructed crossed laser-ion beams apparatus permits us to study photon-negative ion collisions. The highlight of the work has been our photodetachment measurements on Ca/sup /-//. We were able to determine, for the first time, that this ion is stable, being formed in the (4s/sup 2/4p)/sup 2/P state. The electron affinity of Ca (4s/sup 2/ /sup 1/S) was measured to be 43 +- 7 MeV. This result is particularly satisfying since it represents the culmination of early measurements on Ca/sup /-//, including autodetachment studies, which date back to the first proposal and progress reports submitted to DOE in 1984. We have also obtained photoelectron spectra from beams of He/sup /-// and B/sup /-// ions. We have just started a program to measure the angular distribution of photoelectrons detached in photon-negative ion collisions. Preliminary results for the case of the photodetachment of He/sup /-// ions at a photon energy of 590 nm are encouraging. 7 refs., 10 figs.

• Research Organization: Tennessee Univ., Knoxville (USA). Dept. of Physics
• DOE Contract Number: FG05-85ER13456
• OSTI ID: 6967399
• Report Number(s): DOE/ER/13456-12; ON: DE88007996
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
ANGULAR DISTRIBUTION
BORON IONS
CALCIUM IONS
CHARGED PARTICLES
DATA ACQUISITION SYSTEMS
DISTRIBUTION
DOCUMENT TYPES
DYE LASERS
ELECTRON DETACHMENT
ELECTRON SPECTROSCOPY
ENERGY LEVELS
HELIUM IONS
IONS
LASERS
LIQUID LASERS
PHOTOELECTRON SPECTROSCOPY
PROGRESS REPORT
RESEARCH PROGRAMS
SPECTROSCOPY